Various methods for conveying small amounts of data to a mobile reading device are in common use. For example, conventional methods use radio frequency identification (RFID), including near-field communication (NFC) tags, and printed codes, such as linear bar codes and two dimensional codes such as quick response (OR) and DataMatrix codes. Each particular method has potential drawbacks to their use. For example, some can only be read at a particular distance from the tag and some require dedicated reading hardware. Also, passive tags and printed codes cannot be changed once set or printed. Thus, it would be desirable to provide a mechanism to transmit information that does not have these limitations.